1. Field of the Invention
The present invention relates to a motion estimation apparatus and method for moving picture coding and, more particularly, to a motion estimation apparatus and method for efficiently operating a processor in order to conduct moving picture coding based on H.264.
This work was supported by the IT R&D program of MIC/IITA [2007-S026-01, Multi-Format Multimedia SoC based on MPcore Platform].
2. Discussion of Related Art
The international organizations for video coding standards, International Telecommunication Union Telecommunication Standardization Sector (ITU-T) and International Standards Organization (ISO), jointly construct the joint video team (JVT) to issue H.264, which is a standard for video compression. Like known video coding systems, the standard H.264 performs motion estimation on a previous frame that has already been encoded, thereby forming an estimation signal. Further, the standard H.264 mixes motion compensation with discrete cosine transform (DCT), thereby forming an estimation error signal. Here, the standard H.264 conducts the motion estimation up to 4×4 block size, which is smaller than that used in the known coding systems, in order to enhance compression capability, and the motion compensation up to a ¼-pel unit. The video coding standard H.264 based on these technologies has twice as high compression capability as a known video coding standard, Moving Picture Experts Group-4 Advanced Simple Profile (MPEG-4 ASP), has. Accordingly, in the case of the standard H.264, its applications are expected as critical technology to be used for a variety of multimedia communication services. Further, researches for improving technology and capability of compressing video data using an H.264 video codec are actively made.
However, the video codec technology based on the standard H.264 requires wide memory bandwidth and high design complexity when realized, so that it has difficulty in becoming a real-time application. Particularly, since the motion estimation based on the ¼-pel unit is more complicated than that based on the ½-pel unit, efficient pixel interpolation and motion estimation are required.